Why do cryptogams need water for reproduction while phanerogams do not?
Answers
1. A cryptogam (scientific name Cryptogamae) is a plant that reproduces by spores, without flowers or seeds. "Cryptogamae” means hidden reproduction, referring to the fact that no seed is produced, thus cryptogams represent the non-seed bearing plants. The best known groups of cryptogams are algae, lichens, mosses and ferns
2. Flowerless or seedless plants . Lower and more primitive plants. Hidden Reproductive Organs. Reproduction By spores. 3 main groups i.e. Thallophyte, Bryophyte and Pteridophyte Now we would learn about
3. A phylum of plants of very diverse habit and structure. They are unicellular. They reproduce vegetatively or by means of asexual spores. In the higher forms the plant body is a thallus, which may be filamentous or may consist of plates of cells. It is commonly undifferentiated into stem, leaves, and roots, and shows no distinct tissue systems. These are mostly aquatic plants and found both in fresh and marine water.
4. Examples of THALLOPHYTA
5. This division is the simple stand most primitive nonvascular land plant having an embryo. This is the Plant Division that contains mosses. Plants in this Division have crude stems and leaves, but no roots Instead of roots, they have "rhizoids." Rhizoid helps in anchoring the plant to a surface, but they do not absorb nutrients like roots in other plants do. Instead of using flowers to make seeds, mosses release spores from their leaves. Spores can travel by water and make new mosses in new location. Ex:-ricca, liverworts,marchantia,etc.
6. The division include first vascular land plants The plants are saprophytes and made up of true roots and streams. All the plants have vascular tissue. Reproduction occurs by spores produced inside the sporangia Sex organelles are multi cellular and jacketed. The male and female organs are called antheridia and archegonia respectively. Flowers and seeds are not produced. The fertilized eggs develops in embryo.
7. Examples of PTERIDOPHYTA
8. Phanerogamae are seed bearing plants with evident reproductive organs called flowers. On the basis of naked or protected ovules and absence or presence of fruits, the subkingdom Phanerogamae is divided in to two sub-kingdoms. Gymnosperms Angiosperms.
9. The plant body is saprophytic ( diploid ) and differentiated into true stem ,leaves and roots. Vascular tissues are present which forms a vascular system Sex organs are well developed and multicellular. After fertilization, an embryo develops from fertilized egg.
10. Gymnosperms are seed-bearing vascular plants, such as cedar, pine, red-wood trees and conifers, in which the ovules or seeds are not enclosed in an ovary. The word "gymnosperm" comes from the Greek word gymnosperma, meaning "naked seeds". There are around 1000 species of gymnosperm.
11. Examples of GYMNOSPERMS
12. Angiosperms are seed-bearing vascular plants. Their reproductive structures are flowers in which the ovules are enclosed in an ovary. Angiosperms are found in almost every habitat from forests and grasslands to sea margins and deserts. Angiosperms display a huge variety of life forms including trees, herbs, submerged aquatics and bulbs. The are further divided on the basis of number of cotyledons they have. 1.Monocots 2.Dicots
13. Examples of ANGIOSPERMS
14. DIFFERENCE BETWEEN MONOCOTS AND DICOTS Monocots Dicots Embryo with 1 cotyledon, usually developing under ground Embryo with 2 cotyledons, usually developing above ground Roots usually fibrous A primary root usually present Growth is mostly herbaceous Growth either herbaceous or woody Vascular bundles scattered Vascular bundles usually forming a ring Leaves usually parallelveined Leaves usually net-veined Flower parts usually in multiples of 3 Flower parts usually 4 or 5
15. Examples of Dicot and Monocots Monocots Dicots
16. Cryptogams Phanerogams They reproduce by forming spores. They reproduce by forming seeds. Their reproductive organs are hidden. Their reproductive organs are exposed. They are less evolved plants. They are highly evolved plants. Mostly Thallophyta, Bryophyte and Pteridophyta are Cryptogams. All Angiosperms and Gymnosperms are Phanerogams. E.g. mosses, ferns etc. E.g. mango, rose, pine, banyan etc.